Blade driving devices are used to change the state of an opening by driving one or more blade members that advance into the opening, and are used in a variety up optical units, such as cameras, for irises, shutters, iris-shutters, filters, and the like.
Typically the blade driving device is disposed overlapping the lens frame, but a blade driving device that is assembled into the interior of a lens frame, in order to achieve miniaturization or integration, is also known. In such a conventional technology, the blade driving device comprises an insertion portion that has an opening, where the insertion portion is inserted into a slit that is provided in an outer lens barrel of the lens frame (see, Japanese Unexamined Patent Application Publication 2007-271670.